The article of footwear taught in the present invention includes a spring element which can provide improved cushioning, stability, and running economy. Unlike the conventional foam materials presently being used by the footwear industry, a preferred spring element is not substantially subject to compression set degradation and can provide a relatively long service life. The components of the article of footwear including the upper, insole, spring element, and sole can be selected from a range of options, and can be easily removed and replaced, as desired. Further, the relative configuration and functional relationship as between the forefoot, midfoot and rearfoot areas of the article of footwear can be readily modified and adjusted. Accordingly, the article of footwear can be customized by an individual wearer or specially configured for a select target population in order to optimize desired performance criteria. Moreover, the present invention teaches a novel method of manufacturing an article of footwear, and also, a novel way of doing both retail and Internet business.
Conventional athletic footwear typically include an outsole made of a thermoset rubber compound which is affixed by adhesive to a midsole made of ethylene vinyl acetate or polyurethane foam material which is in turn affixed by adhesive to an upper which is constructed with the use of stitching and adhesives. Because of the difficulty, time, and expense associated with renewing any portion of conventional articles of footwear, the vast majority are generally discarded at the end of their service life. This service life can be characterized as having a short duration when a wearer frequently engages in athletic activity such as distance running or tennis. In tennis, portions of the outsole can be substantially abraded within a few hours, and in distance running the foam midsole can become compacted and degrade by taking a compression set within one hundred miles of use. The resulting deformation of the foam midsole can degrade cushioning and footwear stability, thus contribute to the origin of athletic injuries. Accordingly, many competitive distance runners who routinely cover one hundred miles in a week's time will discard their athletic footwear after logging three hundred miles in order to avoid possible injury.
Even though the service life of conventional athletic footwear is relatively short, the price of athletic footwear has steadily increased over the last three decades, and some models now bear retail prices over one hundred and twenty dollars. However, some of this increase in retail prices has been design and fashion driven as opposed to reflecting actual value added. In any case, conventional athletic footwear remain disposable commodities and few are being recycled. The method of manufacture and disposal of conventional athletic footwear is therefore relatively inefficient and not environmentally friendly. In contrast with conventional athletic footwear, the present invention teaches an article of footwear that includes spring elements which do not take a compression set or similarly degrade, thus the physical and mechanical properties afforded by a preferred article of footwear remain substantially the same over a useful service life which can be several times longer than that of conventional articles of footwear. The present invention teaches an article of footwear which represents an investment, as opposed to a disposable commodity. Like an automobile, the preferred article of footwear includes components which can be easily renewed and replaced, but also components which can be varied and customized, as desired.
Published examples of devices and means for selectively and removably affixing various components of an article of footwear include, e.g., U.S. Pat. Nos. 2,183,277, 2,200,080, 2,220,534, 2,552,943, 2,588,061, 2,640,283, 2,873,540, 3,012,340, 3,818,617, 3,878,626, 3,906,646, 3,982,336, 4,103,440, 4,107,857, 4,132,016, 4,262,434, 4,267,650, 4,279,083, 4,300,294, 4,317,294, 4,351,120, 4,377,042, 4,535,554, 4,606,139, 4,807,372, 4,887,369, 5,042,175, 5,083,385, 5,317,822, 5,339,544, 5,410,821, 5,533,280, 5,542,198, 5,615,497, 5,628,129, 5,644,857, 5,657,558, 5,661,915, 5,678,327, 5,692,319, 5,729,916, 5,826,352, 5,896,608, 6,151,805, 6,247,249 B1, 6,282,814 B1, 6,324,772 B1, 6,332,281 B1, and application WO 02/13641 A1, all of these patents and patent applications hereby being incorporated by reference herein.
Conventional athletic footwear cannot be substantially customized for use by the consumer or wearer. The physical and mechanical properties of conventional athletic footwear are relatively fixed generic qualities. However, the body weight or mass and characteristic running technique of different individuals having the same footwear size can vary greatly. Often, the stiffness in compression of the foam material used in the midsole of athletic shoes can be too soft for individuals who employ more forceful movements, or who have greater body mass than an average wearer. Accordingly, conventional articles of athletic footwear do not provide optimal performance characteristics for individual wearers.
In contrast, the present invention permits a wearer to customize a preferred article of footwear. For example, the length, width, girth, and configuration of the upper, as provided by various last options, or by two or three dimensional modeling and footwear design equipment including computer software and data storage systems, or by two or three dimensional measurement devices such as scanners, as well as the type of footwear construction and design of the upper can be selected by the consumer or wearer. Further, the physical and mechanical properties of the article of footwear can be selected and changed as desired in order to optimize desired performance characteristics given various performance criteria or environmental conditions. For example, the configuration and geometry of the article of footwear, and the stiffness of the spring elements can be customized, as desired. In addition, the ability to easily remove, renew, and recycle the outsole portions of the preferred article of footwear can render the use of softer materials having enhanced shock and vibration dampening characteristics, but perhaps diminished wear properties, viable from a practical standpoint. Moreover, the outsole portion of the preferred article of footwear can be selected from a variety of options with regards to configuration, materials, and function.
The physical and mechanical properties associated with an article of footwear of the present invention can provide enhanced cushioning, stability, and running economy relative to conventional articles of footwear. The spring to dampening ratio of conventional articles of footwear is commonly in the range between 40-60 percent, whereas the preferred article of footwear can provide a higher spring to dampening ratio, thus greater mechanical efficiency and running economy. The preferred article of footwear can include an anterior spring element that underlies the forefoot area which can store energy during the latter portion of the stance phase and early portion of the propulsive phase of the running cycle, and then release this energy during the latter portion of the propulsive phase, thus facilitating improved running economy. It is believed the resulting improvement in running performance can approximate one second over four hundred meters, or two to three percent.
The preferred article of footwear can provide differential stiffness in the rearfoot area so as to reduce both the rate and magnitude of pronation, or alternately, the rate and magnitude of supination experienced by an individual wearer, thus avoid conditions which can be associated with injury. Likewise, the preferred article of footwear can provide differential stiffness in the midfoot and forefoot areas so as to reduce both the rate and magnitude of inward and/or outward rotation of the foot, thus avoid conditions which can be associated with injury. The preferred spring elements can also provide a stable platform which can prevent or reduce the amount of deformation caused by point loads, thus avoid conditions which can be associated with injury.
Again, the viability of using relatively soft outsole materials having improved shock and vibration dampening characteristics can enhance cushioning effects. Further, in conventional articles of footwear, the shock and vibration generated during rearfoot impact is commonly transmitted most rapidly to a wearer through that portion of the outsole and midsole which has greatest stiffness, and normally, this is a portion of the sole proximate the heel of the wearer which undergoes the greatest deflection and deformation. However, in the present invention a void space exists beneath the heel of a wearer and the ground engaging portion of the outsole. Some of the shock and vibration generated during the rearfoot impact of an outsole with the ground support surface must then travel a greater distance through the outsole and inferior spring element in order to be transmitted to the superior spring element and a wearer. In addition, in the present invention, a posterior spacer which can serve as a shock and vibration isolator, and also vibration decay time modifiers can be used to decrease the magnitude of the shock and vibration transmitted to the wearer of a preferred article of footwear.
There are many published examples of attempts to introduce functional spring elements into articles of footwear, e.g., U.S. Pat. Nos. 357,062, 1,088,328, 1,107,894, 1,113,266, 1,352,865, 1,370,212, 2,444,865, 2,447,603, 2,456,102, 2,508,318, 3,333,353, 4,429,474, 4,492,046, 4,314,413, 4,486,964, 4,506,460, 4,566,206, 4,771,554, 4,854,057, 4,878,300, 4,942,677, 5,042,175, 5,052,130, 5,060,401, 5,138,776, 5,159,767, 5,203,095, 5,279,051, 5,337,492, 5,343,639, 5,353,523, 5,367,790, 5,381,608, 5,437,110, 5,461,800, 5,528,842, 5,596,819, 5,636,456, 5,647,145, 5,678,327, 5,701,686, 5,729,916, 5,822,886, 5,875,567, 5,937,544, 5,940,994, 6,029,374, 6,195,915, 6,247,249 B1, 6,282,814 B1, 6,327,795, 6,330,757, 6,324,772 B1, French Patent 472,735, Italian Patent 633,409, European Patent Applications EP 0 890 321 A2, EP 1 048 233 A2, EP 1 033 087 A1, EP 1 025 770 A2, and PCT Patent Application WO 98/07341, all of these patents and patent applications hereby being incorporated by reference herein. Relatively few of these attempts have resulted in functional articles of footwear which have met with commercial success. The limitations of some of the prior art has concerned the difficulty of meeting the potentially competing criteria associated with cushioning and footwear stability. In other cases, the manufacturing costs of making prior art articles of footwear including spring elements have proved prohibitive.
The spring element and various other novel structures taught in the present invention can be used in a wide assortment of articles of footwear including but not limited to those used for running, walking, basketball, tennis, volleyball, cross-training, baseball, football, golf, soccer, cycling, sandals, hiking boots, and army boots. The present invention teaches an article of footwear which can provide a wearer with improved cushioning and stability, running economy, and an extended service life while reducing the risks of injury normally associated with footwear degradation. The preferred article of footwear provides a wearer with the ability to customize the fit, but also the physical and mechanical properties and performance of the article of footwear. Moreover, the preferred article of footwear is economical and environmentally friendly to both manufacture and recycle.
The present invention also teaches articles of footwear including means for adjusting the foot shape, length, width, and girth. For example, spring elements, anterior outsole elements, stability elements, and uppers having different configurations, and also alternate positions for selectively affixing various portions of an upper can be used to adjust and customize the fit of an article of footwear for an individual wearer. The upper can also include elastic or elongation means for adjusting the width, girth, and foot shape. The components of the article of footwear possibly including but not limited to the upper, insole, spring element, and sole can be selected from a range of options, and can be easily removed and replaced, as desired. Further, the relative configuration and functional relationship as between the forefoot, midfoot and rearfoot areas of the article of footwear can be readily modified and adjusted. Accordingly, the article of footwear can be configured and customized for a wearer or a select target population in order to optimize performance criteria, as desired.
Moreover, the present invention teaches a novel method of manufacturing articles of footwear, and also, a novel way of doing both retail and Internet business. For example, the anatomical features, configuration, and dimensions of a given wearer's foot and any other special needs, requirements, or preferences can be recorded by direct communication, observation, and measurement in a retail or medical setting, or alternately, by a wearer or other individual within their home or other remote site, and this data can be used to generate information and intelligence relating to the manufacture of a custom article of footwear. Conventional measuring or reproduction means such as rulers, measuring tapes, Brannock devices, two or three dimensional scanners, pressure sensors, infrared thermography, stereolithography, photographs, photocopies, FAX e-mail, cameras, images, tracings, video, television, computers and computer screens, software, data storage and retrieval systems, templates, molds, models, and patterns can be used to help determine and make selections relating to an individual's foot shape, length, width, girth, and the like.
Teachings which have been published or that otherwise constitute public information regarding the conduct of Internet or retail business include: U.S. Pat. No. 5,897,622 granted to Blinn et al.; U.S. Pat. No. 5,930,769 granted to Rose; U.S. Pat. No. 5,983,200 granted to Slotznick; U.S. Pat. No. 5,983,201 granted to Fay; U.S. Pat. No. 6,206,750 B1 granted to Barad et al.; the press release by Nike, Inc. dated Nov. 22, 1999 and the Internet website www.nike.com, and in particular, the section associated with the Nike iD program; the Internet website www.customatix.com; the Internet website www.adidas.com, and in particular, click on “products,” then click on “mass customization,” and see everything related to the “MI Adidas” initiative; and, the publication in the Oakland Tribune on Dec. 18, 1996 relating to the Internet Mall website, and in particular, the Internet website www.copycaps.com. All the patents recited in this paragraph are hereby incorporated by reference herein.
Given the provision of an adequate and ready stock of the various components anticipated for use in making the preferred articles of footwear, and the information and intelligence created from the data relating to an individual wearer or target population, a worker and/or automated system can assemble or manufacture a customized article of footwear within five minutes. In fact, it is possible to assemble a selected and customized article of footwear according to the present invention in less than one minute using a single fastener. This can be accomplished at the point of purchase or service center which can be located in a retail or medical facility, or alternatively, at a remote manufacturing environment. Accordingly, similar to the rapid delivery eyewear service centers and retail stores which presently exist, a consumer can now also be provided with a custom article of footwear within minutes. Alternately, if and when an individual's data is received from a remote site at the Website or other address of a company which practices the present invention, and then transmitted to a manufacturing or assembly center, a custom article of footwear can be made and possibly delivered to an individual's home or other designated address by same day or overnight service, as desired.